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1.
为了更有效地执行我国能效等级评价标准和降低办公能耗,着重讨论了打印设备的能源效率评价。通过收集的数据来分析打印机能效限定值及相应的能效等级标准的测试方法测试过程中的关键点。通过引入计算模型和介绍测量典型能耗分析法(TEC),操作模式功率法(OM)的步骤和检测方法。对检测需要注意的项目以及有效降低电力能源消耗提出对应的方案和建议。  相似文献   

2.
空调能效标准作为产品节能控制的有效手段,已普遍被各国采用。本文针对美国能效标准ARI Standard 210/240-2008~([1])与中国能效标准GB/T 7725-2004~([2])中的季节能效测试及计算方法的差异进行了解析,分析并实验验证了两种标准下的能效值差异,提出国标发展方向建议。通过验证,同一样机美标下得出的制冷季节能效SEER值始终高于国标。国标入门1级能效样品的SEER和HSPF分别高出美国能源之星要求的47.3 %、37.4 %,为国标与美标能效等级的横向对应关系提供参考。  相似文献   

3.
针对城市居住建筑能耗问题,利用相关分析、鱼骨图模型得出城市能耗与影响因素联系程度,并结合SVM原理构建城市能耗预测模型。鱼骨图以城市能耗为原因问题,以城市能耗直接相关的因素作为原因,间接相关作为子原因,相关系数作为联系值,得出相关的关系系数并作为因素权重。以28组工程项目数据作为训练样本,利用SVM模型建立相应的预测模型,并采用平均绝对误差进行评估,再以5组测试样本进行检验。研究结果表明,夏温度设定与各因素的相关性极弱;户主年龄较重要,电脑台数较不重要。  相似文献   

4.
本文介绍的是一种能为与水源连接的电器产品安全及性能测试提供高精度多参数供水系统的研制思路。本系统由PLC(可编程逻辑控制器)、模糊PID(管路及仪表布置图)调节仪、变频器、电动阀、计量泵等组成,实现了供水温度、压力、流量、电阻率、pH值、硬度等多参数的全自动控制。经实际测试,该供水系统各项参数均能达到标准规定的供水要求。  相似文献   

5.
文章介绍了国内外污水处理用旋转曝气机的发展及现状,讲述了制定污水处理用旋转曝气机强制性能效标准的历史背景和依据原则,介绍了旋转式曝气机强制性能效标准的主要内容,旨在通过该标准的实施,普遍提高国产污水处理用旋转曝气机的能效,推动行业技术水平提高并持续发展。  相似文献   

6.
为了利用现有的步入式温度、湿热试验箱进行太阳辐射试验,本文采用一套或两套可移动门架式辐射试验装置来满足测试要求。该装置采用整体或分段式结构,由可移动门架式灯架车、辐射高度角度调节机构、红外线辐照灯组、太阳总辐射表、辐照度采集、记录、辐照强度调节、控制系统等组成。试验结果表明该装置能够模拟太阳辐射,达到测试要求。可以为同类试验箱的加改装提供借鉴。  相似文献   

7.
根据洗衣机能效标准的要求,基于对波轮洗衣机洗净率测试的不确定度的分析和计算,通过试验及实测数据总结其不确定因素的来源情况和影响程度,并提出能有效提高测量精度,降低不确定因素的相关措施,进一步增加测量值的确定性和准确性。  相似文献   

8.
面对航空航天、国防和汽车等工业领域对复杂薄壁铸件的需求,本次研究了基于PLC可编程序控制器的件数差压铸造电气控制系统。该系统主要针对传统差压铸造电气控制系统资源利用率低、吞吐量性能差的问题,利用PLC控制器改善其性能。系统按照B/S结构将分为采集层、传输层以及主控层三个层次,首先利用采集层中的绝压传感器和表压传感器采集差压铸造设备中的压力值,并对其进行转换和滤波处理,然后将压力数据通过CAN总线传输到主控层当中,利用PLC可编程序控制器对数据进行分析、结果显示等,判断数值是否超过预设值,并根据结果利用调节阀进行相应的执行操作。结果表明:与传统差压铸造电气控制系统相比,基于PLC可编程序控制器的件数差压铸造电气控制系统的资源利用率更高,系统吞吐量性能更好。  相似文献   

9.
为了提高试验箱温度控制系统的精准度,缩短系统调节时间,提出了一种基于改进的麻雀搜索算法优化PID控制参数的方法(ISSA-PID)。利用PWLCM混沌映射初始化麻雀种群,丰富麻雀种群的多样性,采用Levy飞行策略改进了SSA算法种群中发现者和警戒者的位置更新方程,避免算法陷入局部最优,建立了试验箱加热温度控制系统的数学模型,利用改进的麻雀搜索算法(ISSA)优化了其模型PID控制参数。分别采用试凑法、麻雀搜索算法和ISSA算法对试验箱加热温度控制系统的PID控制参数进行了优化并对其仿真分析。仿真结果表明,ISSA算法使得控制系统超调量减少了18.9%,系统调节时间减少了704s,并利用PLC、触摸屏和试验箱搭建的实验装置开展实际实验测试。通过仿真和实验表明,ISSA算法对PID控制参数的优化效果更佳,且验证了ISSA算法优化PID控制参数在试验箱中应用的可行性。  相似文献   

10.
热电偶作为检测实验室的一种基础耗材,被广泛用于电子电器产品、新能源产品等的安全、能效测试中。目前,测试实验室在用热电偶一般采用抽样的方式送计量,故而不能确保全部热电偶的精度。针对这一现状,本文提出了一种高效便捷的热电偶期间核查方法。以自然界容易获得的0℃和100℃为标准温度基准,确定被测热电偶和该标准温度基准的偏差,判定其合格率。该方法可方便快捷的对热电偶进行期间核查,促进实验室基础耗材质量控制。  相似文献   

11.
Fire and logging in nutrient-poor temperate forests with certain ericaceous understory plants may convert the forests into heaths. The process of disturbance-induced heath formation is documented by using examples ofCalluna in western Europe,Kalmia in Newfoundland, andGaultheria (salal) in coastal British Columbia. In a cool, temperate climate, rapid vegetative growth ofCalluna, Kalmia, and salal following disturbance results in increasing organic accumulation (paludification), nutrient sequestration, soil acidification, and allelochemicals. These are thought to be the main reasons to conifer regeneration failure in disturbed habitats. If continuation in forest is a land-use objective, then temperate forests with an ericaceous understory should not be logged unless effective silvicultural methods are devised to control the ericaceous plants and restore forest regeneration. Preharvest vegetation control may be considered as an option. Failure to control the understory plants may lead to a long-term vegetation shift, from forest to heathland, particularly in nutrient-poor sites. Successful methods of controllingKalmia andGaultheria, however, have yet to be developed. While theKalmia- andGaultheria- dominated heathlands are undesirable in Canada and the Pacific Northwest, a wide range ofCalluna heathlands of western Europe are being conserved as natural and seminatural vegetation.  相似文献   

12.
Urban ecological systems: scientific foundations and a decade of progress   总被引:9,自引:0,他引:9  
Urban ecological studies, including focus on cities, suburbs, and exurbs, while having deep roots in the early to mid 20th century, have burgeoned in the last several decades. We use the state factor approach to highlight the role of important aspects of climate, substrate, organisms, relief, and time in differentiating urban from non-urban areas, and for determining heterogeneity within spatially extensive metropolitan areas. In addition to reviewing key findings relevant to each state factor, we note the emergence of tentative "urban syndromes" concerning soils, streams, wildlife and plants, and homogenization of certain ecosystem functions, such as soil organic carbon dynamics. We note the utility of the ecosystem approach, the human ecosystem framework, and watersheds as integrative tools to tie information about multiple state factors together. The organismal component of urban complexes includes the social organization of the human population, and we review key modes by which human populations within urban areas are differentiated, and how such differentiation affects environmentally relevant actions. Emerging syntheses in land change science and ecological urban design are also summarized. The multifaceted frameworks and the growing urban knowledge base do however identify some pressing research needs.  相似文献   

13.
Urban gardens are important sources of sustenance for communities with limited access to food. Hence, this study focuses on food production in gardens in the Toledo metropolitan area in Northwest Ohio. We administered surveys to 150 garden managers from November 2014 to February 2015 in our attempt to better understand how neighbourhood racial composition and poverty levels are related to staffing and voluntarism, food production and distribution, the development of infrastructure, and the adoption of sustainability practices in urban gardens. The results from 30 gardens are presented in this paper. We used Geographic Information Systems to map the gardens and overlay the map with 2010 census data so that we could conduct demographic analyses of the neighbourhoods in which the gardens were located. Though the gardens were small – two acres or less – up to 46 varieties of food were grown in a single garden. Gardens also operated on small budgets. Food from the gardens was gifted or shared with friends, family, and neighbourhood residents. Gardens in predominantly minority neighbourhoods tended to have fewer institutional partners, less garden infrastructure, and had adopted fewer sustainable practices than gardens in predominantly White neighbourhoods. Nonetheless, residents of predominantly minority and high-poverty neighbourhoods participated in garden activities and influenced garden operations. Volunteering and staffing were racialised and gendered.  相似文献   

14.
Collisions with deer and other large animals are increasing, and the resulting economic costs and risks to public safety have made mitigation measures a priority for both city and wildlife managers. We created landscape models to describe and predict deer-vehicle collision (DVCs) within the City of Edmonton, Alberta. Models based on roadside characteristics revealed that DVCs occurred frequently where roadside vegetation was both denser and more diverse, and that DVCs were more likely to occur when the groomed width of roadside right-of-ways was smaller. No DVCs occurred where the width of the vegetation-free or manicured roadside buffer was greater than 40 m. Landscape-based models showed that DVCs were more likely in more heterogeneous landscapes where road densities were lower and speed limits were higher, and where non-forested vegetation such as farmland was in closer proximity to larger tracts of forest. These models can help wildlife and transportation managers to identify locations of high collision frequency for mitigation. Modifying certain landscape and roadside habitats can be an effective way to reduce deer-vehicle collisions.  相似文献   

15.
Water treatment residuals (WTR) can reduce runoff P loss and surface co-application of P-sources and WTR is a practical way of land applying the residuals. In a rainfall simulation study, we evaluated the effects of surface co-applied P-sources and an Al-WTR on runoff and leacheate bioavailable P (BAP) losses from a Florida sand. Four P-sources, namely poultry manure, Boca Raton biosolids (high water-soluble P), Pompano biosolids (moderate water-soluble P), and triple super phosphate (TSP) were surface applied at 56 and 224kgPha(-1) (by weight) to represent low and high soil P loads typical of P- and N-based amendments rates. The treatments further received surface applied WTR at 0 or 10gWTRkg(-1) soil. BAP loss masses were greater in leachate (16.4-536mg) than in runoff (0.91-46mg), but were reduced in runoff and leachate by surface applied WTR. Masses of total BAP lost in the presence of surface applied WTR were less than approximately 75% of BAP losses in the absence of WTR. Total BAP losses from each of the organic sources applied at N-based rates were not greater than P loss from TSP applied at a P-based rate. The BAP loss at the N-based rate of moderate water-soluble P-source (Pompano biosolids) was not greater than BAP losses at the P-based rates of other organic sources tested. The hazards of excess P from applying organic P-sources at N-based rates are not greater than observed at P-based rates of mineral fertilizer. Results suggest that management of the environmental P hazards associated with N-based rates of organic materials in Florida sands is possible by either applying P-sources with WTR or using a moderate water-soluble P-source.  相似文献   

16.
The interactions between humans, animals and the environment have shaped human values and ethics, not only the genes that we are made of. The animal rights movement challenges human beings to reconsider interactions between humans and other animals, and maybe connected to the environmental movement that begs us to recognize the fact that there are symbiotic relationships between humans and all other organisms. The first part of this paper looks at types of bioethics, the implications of autonomy and the value of being alive. Then the level of consciousness of these relationships are explored in survey results from Asia and the Pacific, especially in the 1993 International Bioethics Survey conducted in Australia, Hong Kong, India, Israel, Japan, New Zealand, The Philippines, Russia, Singapore and Thailand. Very few mentioned animal consciousness in the survey, but there were more biocentric comments in Australia and Japan; and more comments with the idea of harmony including humans in Thailand. Comparisons between questions and surveys will also be made, in an attempt to describe what people imagine animal consciousness to be, and whether this relates to human ethics of the relationships. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

17.
This study demonstrates the integration of rehabilitation and flood management planning in a steep, boulder-bedded stream in a coastal urban catchment on the South Island of New Zealand. The Water of Leith, the primary stream flowing through the city of Dunedin, is used as a case study. The catchment is steep, with a short time of concentration and rapid hydrologic response, and the lower stream reaches are highly channelized with floodplain encroachment, a high potential for debris flows, significant flood risks, and severely degraded aquatic habitat. Because the objectives for rehabilitation and flood management in urban catchments are often conflicting, a number of types of analyses at both the catchment and the reach scales and careful planning with stakeholder consultation were needed for successful rehabilitation efforts. This included modeling and analysis of catchment hydrology, fluvial geomorphologic assessment, analysis of water quality and aquatic ecology, hydraulic modeling and flood risk evaluation, detailed feasibility studies, and preliminary design to optimize multiple rehabilitation and flood management objectives. The study showed that all of these analyses were needed for integrated rehabilitation and flood management and that some incremental improvements in stream ecological health, aesthetics, and public recreational opportunities could be achieved in this challenging environment. These methods should be considered in a range of types of stream rehabilitation projects.  相似文献   

18.
ABSTRACT: This paper presents a statistically valid index for measuring the performance of irrigation systems. The index is applied to a sample of 39 farms on a watercourse under the warabandi system of irrigation management in India. It is found that while the farmers in fact irrigated almost exactly the total amount of irrigated area as designed, inter-farm variations were considerable. The index shows that the degree of error of managerial effectiveness of irrigation on this watercourse is 20 percent. Therefore it is concluded that the system is performing at 80 percent effectiveness.  相似文献   

19.
Infiltration models are based on physical characteristics of the soil and initial soil moisture. For a given soil it is based on the initial soil moisture distribution. A computer simulation model for flood runoff systems (FH-Model) was used to analyze 39 sets of rainfall-runoff data on four small watersheds ranging in size from 17 to 342 square kilometers located in the Yamaska River basin in Quebec. From these analyses, parameters and coefficients have been determined for a water loss (infiltration) equation. A method for determining the loss parameters, using a nonlinear least square curve fitting technique, is presented. Expressions were made to relate the loss parameters to antecedent precipitation. The equations were tested on 11 storm rainfall and runoff events on a watershed located in the same region and close agreements were found.  相似文献   

20.
Data are presented on the vegetation dynamics of two impounded marshes along the Indian River Lagoon, in east-central Florida, USA. Vegetation in one of the marshes (IRC 12) was totally eliminated by overflooding and by hypersaline conditions (salinities over 100 ppt) that developed there in 1979 after the culvert connecting the marsh with the lagoon was closed. Over 20% recovery of the herbaceous halophytesSalicornia virginica, S. bigelovii, andBatis maritima was observed at that site after the culvert was reopened in 1982, but total cover in the marsh remains well below the original 75%. No recovery of mangroves was observed at this site. The second site (SLC 24), while remaining isolated from the lagoon during much of the study, did not suffer the complete elimination of vegetation experienced at the first site. At this location, mangroves increased in cover and frequency with a concomitant decrease in herbaceous halophytes. Considerable damage to the vegetation was evident at IRC 12 when the impoundment was closed and flooded for mosquito control in 1986. Although the damage was temporary, its occurrence emphasizes the need of planning and constant monitoring and adjustment of management details as conditions within particular marshes change. Storms and hurricanes may be important in promoting a replacement of black mangroves by red mangroves in closed impoundments because the former cannot tolerate pneumatophore submergence for long periods of time. University of Florida-IFAS Journal Series R-00521.  相似文献   

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